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What is NSArray in Swift?

What is NSArray in Swift?

NSArray is an immutable Objective C class, therefore it is a reference type in Swift and it is bridged to Array . NSMutableArray is the mutable subclass of NSArray .

What is NSMutableArray?

The NSMutableArray class declares the programmatic interface to objects that manage a modifiable array of objects. This class adds insertion and deletion operations to the basic array-handling behavior inherited from NSArray . NSMutableArray is “toll-free bridged” with its Core Foundation counterpart, CFMutableArray .

What is NSMutableSet?

Overview. The NSSet , NSMutableSet , and NSCountedSet classes declare the programmatic interface to an unordered collection of objects. NSSet declares the programmatic interface for static sets of distinct objects. You establish a static set’s entries when it’s created, and can’t modify the entries after that.

How do you declare an array of objects in Objective C?

Creating an Array Object For example: NSArray *myColors; myColors = [NSArray arrayWithObjects: @”Red”, @”Green”, @”Blue”, @”Yellow”, nil]; The above code creates a new array object called myColors and initializes it with four constant string objects containing the strings “Red”, “Green”, “Blue” and “Yellow”.

What is NSMutableString?

NSMutableString is the abstract base class for a cluster of classes representing strings whose contents can be changed. It inherits from NSString. It extends the interface it inherits from NSString by adding methods to change the string contents.

Which is faster to iterate through an NSArray or a NSSet?

Yes, NSArray is faster than NSSet for simply holding and iterating. As little as 50% faster for constructing and as much as 500% faster for iterating. Lesson: if you only need to iterate contents, don’t use an NSSet.

Which is faster array or set Swift?

Array is faster than set in terms of initialization. Set is slower than an array in terms of initialization because it uses a hash process. The array allows to store duplicate elements in it.

What is NSCoding protocol?

The NSCoding protocol declares the two methods that a class must implement so that instances of that class can be encoded and decoded. This capability provides the basis for archiving (where objects and other structures are stored on disk) and distribution (where objects are copied to different address spaces).

What is Nsobject protocol?

This protocol is imported into Swift with the name NSObjectProtocol . An object that conforms to this protocol can be considered a first-class object. Such an object can be asked about its: Class, and the place of its class in the inheritance hierarchy.

What is the difference between NSArray and NSSet?

The main difference is that NSArray is for an ordered collection and NSSet is for an unordered collection.

What is an NSArray in Java?

Remember that NSArray is the public interface for a class cluster and what this entails for your subclass. You must provide the storage for your subclass and implement the primitive methods that directly act on that storage.

How do I initialize an NSArray class?

If you do, your initializer must invoke one of the designated initializers of the NSArray class, either init () or init (objects:count:). The NSArray class adopts the NSCopying, NSMutableCopying, and NSCoding protocols; custom subclasses of NSArray should override the methods in these protocols as necessary.

How do I override primitive instance methods of an NSArray?

Any subclass of NSArray must override the primitive instance methods count and object (at:). These methods must operate on the backing store that you provide for the elements of the collection. For this backing store you can use a static array, a standard NSArray object, or some other data type or mechanism.

Is NSArray toll free bridging?

NSArray is “toll-free bridged” with its Core Foundation counterpart, CFArray. See Toll-Free Bridging for more information on toll-free bridging. In addition to the provided initializers, such as initWithObjects:, you can create an NSArray object using an array literal.